As a frequent traveler and gadget enthusiast, portable power sources are an indispensable staple in my gear pack. And green energy? I can get behind that. That's what makes the BirkSun Atlas ($160 direct) so ingenious—the backpack features a built-in solar panel and portable battery for keeping all of your electronics juiced up on the go, even if your adventures take you off the beaten path. Personally, I think it's a bit overwrought and boxy for my daily city commute, but for traveling or excursions into the wild, it's hard to imagine a better gadget-friendly pack than the Atlas.

//Compare Similar Products

Design and FeaturesAesthetically speaking, the Atlas isn't going to win any awards. The squared-off edges make it look too boxy, and the cotton/poly blend material has an odd sheen—like an imitation waxed canvas. Aside from the prominent solar panel, the Atlas is devoid of design flourishes, which minimalists will appreciate. I'm all for the solar panel, but I have to admit that I felt a bit silly toting it around in the subway for my daily commute.

At 18 by 13 by 6 inches (HWD) with a 20-liter carrying capacity, the Atlas isn't a very large backpack, but the boxy design makes it look a good deal bulkier than it is. Luckily, all the components inside don't add too much weight. The Atlas weighs only 2.2 pounds, which is on par with the 2.2-pound Booq Boa Squeeze—a backpack billed as a thin-and-light commuter pack.

The straps and padding are pretty minimal. It's not entirely uncomfortable, but with the main compartment loaded up, I could feel the relatively thin straps starting to strain my shoulders. Those straps can also be a bit unwieldy, and I routinely found them flipping the wrong way when pulling them over my shoulders. The back panel has some padding and a few ridges running up and down its length, but I found that the flat, boxy design trapped in heat against my back.

The main compartment is covered by a large flap that houses the solar panel. It closes with both Velcro and two adjustable buckles. It stays securely shut, but the buckles and Velcro can make it a bit cumbersome to open and close the pack. There's a side zipper for quickly accessing the front compartment, and plenty of organizational pockets for pens, change, and various small items you typically throw into your bag.

Open the flap and you'll find a fairly spacious main compartment with a pouch for laptops up to 17 inches. I tested it with a 15-inch Apple MacBook Pro and a chunky Lenovo ThinkPad L420, both of which fit fine. Also inside the main compartment is a small pocket that houses the built-in battery pack. Above it are two wires: one mini USB cable that feeds solar power to the battery and one full-size USB port that feeds power from the battery to the embedded cable in the front compartment. BirkSun includes a small pouch with micro USB, mini USB, and Apple 30-pin and Lightning adapters.

PerformanceI took the Atlas on a recent camping trip to see if it could deliver on its solar-powered promise. On a hot and sunny day, the Atlas fully charged the built-in battery in about two hours. The 2,400mAh battery was able to take an Apple iPhone 4S from dead to full charge with some juice to spare. Once the battery is drained, however, the flow of juice is too slow to keep charging devices consistently—you'll have to let the battery refill before you plug another device in. You also shouldn't keep devices plugged in with the bag in direct sun on a hot day. In my tests, if I left the bag and device out in the sun, I'd get an overheating warning on the iPhone. The Atlas worked fine for charging up a variety of smartphones, but the battery's output is limited to 0.8-amps, meaning it can't effectively charge larger tablets like the Apple iPad. Luckily, you can daisy chain a more powerful battery, like the Iogear Gear Power, to the Atlas's own battery for extra juice and higher output for tablets.

At $160, the Atlas may seem a bit pricey, but when you factor in the solar panel and portable battery, it's actually a pretty solid deal. To put it in perspective, a bag like the Boa Squeeze costs $129.99, and a solar charging battery like the Joos Orange Solar Charger will run you $149. My main complaints with the Atlas lie in its design, which is admittedly a matter of personal preference. If you can live with the look and like to carry a healthy stable of gadgets, the BirkSun Atlas is an excellent choice.

PCMag may earn affiliate commissions from the shopping links included on this page. These commissions do not affect how we test, rate or review products. To find out more, read our complete terms of use.

Before joining the consumer electronics team at PCMag, Eugene worked at local news station NY1 doing everything from camera work to writing scripts. He grew up in Montclair, New Jersey and graduated from the University of Virginia in 2010. Outside of work Eugene enjoys TV, loud music, and making generally healthy and responsible life choices.
More »